Conductive pattern

ABSTRACT

Provided is a conductive pattern having at least one unit conductive pattern forming one touch pixel according to an aspect of the present invention. The at least one unit conductive pattern includes a plurality of nanostructures each having opposite ends. A ratio of nanostructures, both opposite ends of which are in contact with edges of the at least one unit conductive pattern to all nanostructures included in the at least one unit conductive pattern is 70% or more.

TECHNICAL FIELD

The present invention relates to a conductive pattern, and moreparticularly, to a conductive pattern capable of improving conductivityand preventing an electrical disconnection error from occurring due tocracks.

BACKGROUND ART

Recently, a touch panel has been applied to various electronic products,through which a user input is input by touching an image displayed on adisplay device with a finger or an input device such as a stylus.

Such touch panels may be largely divided into a resistive-film typetouch panel and a capacitive touch panel. A touched position on theresistive-film type touch panel is detected as glass and an electrodeare shorted by pressure applied by an input device. A touched positionon the capacitive touch panel is detected by sensing a change in acapacitance between electrodes, caused when the touch pad is touched bya finger.

As the resistive-film type touch panel is repeatedly used, theperformance of the touch panel may be lowered and the touch panel may bescratched. Thus, much attention has been paid to capacitive touch panelshaving high durability and long lifetime.

The capacitive touch panel is defined as having an effective region intowhich a touch command may be input and an ineffective region outside theeffective region. In the effective region, an electrode pattern isformed of a transparent conductive material to transmit light from adisplay device.

Conventionally, the electrode pattern is formed of an indium-tin oxide(ITO). The ITO is limited in terms of a high sheet resistance, highmanufacturing costs, and imbalance between the supply and demand ofindium in a raw material market. Furthermore, the ITO is not availablefor a flexible display apparatus which is a recent trend.

Recently, research has been conducted on a transparent electrodematerial such as silver nanowire which may replace the ITO.

FIG. 1 is a diagram illustrating a transparent electrode formed ofconventional silver nanowires.

Referring to FIG. 1, a conventional transparent conductive sheet Aincludes silver nanowires NW. The silver nanowires NW are limited interms of an aspect ratio and are manufactured having a small diameter ofabout 100 nm to achieve high transmissivity. Thus, the silver nanowiresNW having a relatively small length of 5 um to 10 um are applied to atransparent conductive sheet A.

A transparent electrode B is formed by patterning the transparentconductive sheet A according to a certain width. The transparentelectrode B includes a plurality of silver nanowires NW. The silvernanowires NW of the transparent electrode B are short and thus manydisconnections occur between the silver nanowires NW, thereby loweringconductivity.

Furthermore, the transparent electrode B is disadvantageous in that itmay be electrically open due to cracks occurring due to external shocks.

DISCLOSURE Technical Problem

The present invention is directed to a conductive pattern capable ofimproving conductivity while maintaining optical transmissivity.

The present invention is also directed to a conductive pattern capableof reducing manufacturing costs.

The present invention is also directed to a conductive pattern capableof preventing cracks from occurring and preventing electricaldisconnection from occurring even when cracks occur,

Aspects of the present invention are not limited thereto, and additionalaspects will be apparent to those of ordinary skill in the art from thefollowing description and the appended drawings.

Technical Solution

One aspect of the present invention provides a conductive pattern havingat least one unit conductive pattern forming one touch pixel. The atleast one unit conductive pattern includes a plurality of nanostructureseach having opposite ends. A ratio of nanostructures, both opposite endsof which are in contact with edges of the at least one unit conductivepattern to all nanostructures included in the at least one unitconductive pattern is 70% or more.

Advantageous Effects

According to the present invention, a ratio of nanostructures, oppositeends of which intersect side surfaces of a conductive pattern to allnanostructures of the conductive pattern may be set to be high so as toincrease the number of intersection regions between the nanostructures,thereby increasing conductivity.

According to the present invention, intersecting nanostructures of theconductive pattern may be electrically connected to each other duringremoving of a polymer. Accordingly, an additional process may be skippedand thus manufacturing costs may be reduced.

According to the present invention, a ratio of nanostructures, oppositeends of which intersect side surfaces of connection parts tonanostructures of the connection parts in which cracks are likely tooccur may be set to be high. Thus, the occurrence of cracks may bereduced, and an electrical disconnection error may be prevented fromoccurring even when cracks occur.

Effects of the present invention are not, however, limited thereto, andadditional effects will be apparent to those of ordinary skill in theart from the following description and the appended drawings.

DESCRIPTION OF DRAWINGS

FIG. 1 is a diagram illustrating a transparent electrode formed ofconventional silver nanowires.

FIG. 2 is an exploded perspective view of a touch panel according to anembodiment.

FIG. 3 is a top view of a touch panel according to an embodiment.

FIG. 4 is an enlarged view of a first electrode pattern according to anembodiment.

FIG. 5 is a side view of an electrode pattern according to anembodiment, when viewed at a point P.

FIG. 6 is a diagram illustrating a field emission device according to anembodiment.

FIG. 7 is a perspective view of a display device to which a touch panelis applied, according to an embodiment.

MODES OF THE INVENTION

Embodiments set forth herein are provided to clearly explain the idea ofthe present invention to those of ordinary skill in the technical fieldto which the invention pertains. Thus, the present invention is notlimited by these embodiments. The scope of the present invention shouldbe understood to include changed examples or modified examples whichfall within the idea of the present invention.

In the present disclosure, general terms that have been widely usednowadays are selected, if possible, in consideration of functions of thepresent invention, but non-general terms may be selected according tothe intentions of those of ordinary skill in the art, precedents, or newtechnologies, etc. Also, some terms may be arbitrarily chosen by thepresent applicant. In this case, the meanings of these terms will beexplained in corresponding parts of the present disclosure in detail.Thus, the terms used herein should be defined not based on the namesthereof but based on the meanings thereof and the whole context of thepresent invention.

The appended drawings are provided to easily explain the presentinvention, in which the shape of each of elements may be exaggerated forclarity. Thus, the present invention should not be construed as beinglimited thereby.

In the following description, well-known functions or constructions arenot described in detail if it is determined that they would obscure theinvention due to unnecessary detail.

A conductive pattern having at least one unit conductive pattern formingone touch pixel according to an aspect of the present invention isprovided. The at least one unit conductive pattern includes a pluralityof nanostructures each having opposite ends. A ratio of nanostructures,both opposite ends of which are in contact with edges of the at leastone unit conductive pattern to all the nanostructures included in the atleast one unit conductive pattern is 70% or more.

The conductive pattern may include connection parts connecting adjacentunit conductive patterns among the at least one unit conductive pattern.A ratio of nanostructures, both opposite ends of which are in contactwith edges of the connection parts to all the nanostructures included inthe connection parts may be different from that of the nanostructures,both opposite ends of which are in contact with the edges of the atleast one unit conductive pattern to all the nanostructures included inthe at least one unit conductive pattern.

The ratio of the nanostructures, both opposite ends of which are incontact with the edges of the connection parts to all the nanostructuresincluded in the connection parts may be 80% or more.

A width of the connection parts may be 50% to 60% of that of the atleast one unit conductive pattern.

The nanostructures may include a silver (Ag) material.

The nanostructures may be formed by electro-spinning.

The conductive pattern may include a matrix having the plurality ofnanostructures.

The ends of the nanostructures which are in contact with the edges ofthe at least one unit conductive pattern may be exposed to the outsideof the matrix.

The matrix may include a conductive material.

The matrix may prevent the plurality of nanostructures from beingoxidized.

The nanostructures, both opposite ends of which are in contact with theedges of the at least one unit conductive pattern may intersect astraight line connecting the opposite ends at at least one point.

A conductive pattern according to an embodiment of the present inventionwill be described below.

FIG. 2 is an exploded perspective view of a touch panel according to anembodiment.

Referring to FIG. 2, a touch panel 1 according to an embodiment mayinclude a cover substrate 10, a first substrate 20, a second substrate30, and a printed circuit board 40.

The second substrate 30 is located below the cover substrate 10. Thefirst substrate 20 is located below the second substrate 30.

The cover substrate 10 may be attached to the second substrate 30. Thecover substrate 10 and the second substrate 30 may be adhered to eachother using an adhesive substance such as an optical clear adhesive(OCA).

The first substrate 20 may be attached to the second substrate 30. Thefirst substrate 20 and the second substrate 30 may be adhered to eachother using an adhesive substance such as the OCA.

The cover substrate 10 may include glass or plastic. The cover substrate10 may include tempered glass, semi-tempered glass, soda-lime glass,reinforced plastic, or soft plastic.

The first substrate 20 and the second substrate 30 may include plasticsuch as polyethylene terephthalate (PET).

Electrode patterns and wire patterns may be formed on the firstsubstrate 20 and the second substrate 30.

A first electrode pattern 21 and a first wire pattern 25 may be formedon the first substrate 20. A second electrode pattern 31 and a secondwire pattern 35 may be formed on the second substrate 30.

The first electrode pattern 21 may be formed in a first direction. Thefirst electrode pattern 21 may be electrically connected to the firstwire pattern 25.

The second electrode pattern 31 may be formed in a second direction. Thesecond direction may cross the first direction. The second electrodepattern 31 may be formed in a direction crossing the first electrodepattern 21. The second electrode pattern 31 may be electricallyconnected to the second wire pattern 35.

The printed circuit board 40 may be attached to the first substrate 20and the second substrate 30. The printed circuit board 40 may beattached to one side of each of the first substrate 20 and the secondsubstrate 30. The printed circuit board 40 may be attached to the oneside of each of the first substrate 20 and the second substrate 30 to beelectrically connected to the first wire pattern 25 and the second wirepattern 35. An anisotropic conductive film (ACF) may be applied onto theone side of each of the first substrate 20 and the second substrate 30attached to the printed circuit board 40. The printed circuit board 40may apply a voltage to the first wire pattern 25 and the second wirepattern 35 through the ACF.

The printed circuit board 40 may be a flexible printed circuit board(FPCB). The printed circuit board 40 may include a controller whichreceives a sensing signal from the first and second electrode patterns21 and 31 via the first and second wire patterns 25 and 35 and controlsthe sensing signal.

FIG. 3 is a top view of a touch panel according to an embodiment.

Referring to FIG. 3, the touch panel according to an embodiment mayinclude an effective region AA and an ineffective region UA.

The effective region AA may be understood as a region to which a touchcommand may be input by a user. The ineffective region UA may beunderstood as a region which is located outside the effective region AAand to which a touch command is not input since this region is notactivated even when it is touched by the user.

When the touch panel is used while being attached to a display panel,the effective region AA and the ineffective region UA of the touch panelmay respectively correspond to a display region and a non-display regionof the display device. An image is displayed in the display region. Noimage is displayed in the non-display region. Thus, the effective regionAA of the touch panel may include a region which transmits light. Theineffective region UA of the touch panel may include a region which doesnot transmit light.

A plurality of electrode patterns may be formed in the effective regionAA. A plurality of first electrode patterns 21 may be formed in theeffective region AA of the first substrate 20. A plurality of secondelectrode patterns 31 may be formed in the effective region AA of thesecond substrate 30.

Each of the first electrode pattern 21 and the second electrode pattern31 may include a plurality of body regions and a plurality of connectionparts. The body regions may be arranged in one direction. The connectionparts may connect adjacent body regions to each other.

The first electrode pattern 21 may include first body regions 22 andfirst connection parts 23. The first body regions 22 may be arranged ina first direction. The first connection parts 23 may connect first bodyregions 22 adjacent in the first direction to other. The first bodyregions 22 and the first connection parts 23 may be integrally formed.

The second electrode pattern 31 may include second body regions 32 andsecond connection parts 33. The second body regions 32 may be arrangedin a second direction crossing the first direction. The secondconnection parts 33 may connect second body regions 32 adjacent in thesecond direction to each other. The second body regions 32 and thesecond connection parts 33 may be integrally formed.

Each of the first body regions 22 and the second body regions 32 may bedefined as a unit conductive pattern. A touch pixel may include at leastone among the unit conductive patterns.

The first connection parts 23 and the second connection parts 33 may beformed to intersect each other. The first connection parts 23 and thesecond connection parts 33 are formed on different substrates and arethus electrically open.

A plurality of wire patterns may be formed in the ineffective region UA.A plurality of first wire patterns 25 may be formed in the ineffectiveregion UA of the first substrate 20. A plurality of second wire patterns35 may be formed in the ineffective region UA of the second substrate30.

The first electrode pattern 21 may be electrically connected to thefirst wire pattern 25. The first electrode pattern 21 may be integrallyformed with the first wire pattern 25. Alternatively, the firstelectrode pattern 21 may be formed separately from the first wirepattern 25.

The second electrode pattern 31 may be electrically connected to thesecond wire pattern 35. The second electrode pattern 31 may beintegrally formed with the second wire pattern 35. Alternatively, thesecond electrode pattern 31 may be formed separately from the secondwire pattern 35.

The first and second electrode patterns 21 and 31 and the first andsecond wire patterns 25 and 35 may include a conductive material. Thefirst and second electrode patterns 21 and 31 may be formed of atransparent conductive material.

FIG. 4 is an enlarged view of a first electrode pattern according to anembodiment. FIG. 5 is a side view of an electrode pattern according toan embodiment, when viewed at a point P.

Referring to FIGS. 4 and 5, the first electrode pattern 21 according toan embodiment may include a first body region 22 and a first connectionpart 23.

The first electrode pattern 21 may include a plurality of nanostructures50 and a matrix 55.

The nanostructures 50 may be nanofibers having an aspect ratio of100,000 or more. The nanostructures 50 may have a width of 1 um or less.The nanostructures 50 may be formed in a cylindrical shape.

The nanostructures 50 may include a metal material. Examples of themetal material may include silver, gold, copper, nickel, gold-platedsilver, platinum, and palladium. When the nanostructures 50 includesilver, the nanostructures 50 may be defined as silver nanostructures.Alternatively, the nanostructures 50 may be formed of only a metalmaterial.

The nanostructures 50 are formed as having a small width and cannot bethus viewed with a naked eye. The first electrode pattern 21 includingthe nanostructures 50 is guaranteed having high optical transmissivity.

The matrix 55 is referred to as a solid-state material forming a mainbody of the first electrode pattern 21, in which the nanostructures 50are dispersed or included therein.

The matrix 55 may protect the nanostructures 50 from the outside. Thematrix 55 may prevent the nanostructures 50 from being oxidized. Thematrix 55 may provide adhesive strength so that the first electrodepattern 21 may be attached to the first substrate 20.

The nanostructures 50 may be in direct contact with the matrix 55. Thatis, outer surfaces of the nanostructures 50 may be in direct contactwith the matrix 55.

The matrix 55 may include a conductive polymer. When the matrix 55includes the conductive polymer, the matrix 55 may provide a chargemoving path. As the matrix 55 provides the charge moving path, thematrix 55 may serve as an auxiliary electrode.

The conductive polymer may include, but is not limited to,polyacetylene, polythiophene, polypyrrole, polyparaphenylene,polyparaphenylene vinylene, PEDOT:PSS, carbon nanotubes, or the like.

The first body region 22 may have a tetragonal shape. The first bodyregion 22 may have four side surfaces. The first body region 22 may havea first side surface 22 a, a second side surface 22 b, a third sidesurface 22 c, and a fourth side surface 22 d. The first side surface 22a is defined as a surface facing the third side surface 22 c. The secondside surface 22 b is defined as a surface facing the fourth side surface22 d. The second side surface 22 b is a surface adjacent to the firstside surface 22 a and the third side surface 22 c. The fourth sidesurface 22 d is a surface adjacent to the first side surface 22 a andthe third side surface 22 c.

The first to fourth side surfaces 22 a to 22 d may be cross sectionspatterned by a photolithographic process.

Similarly, the nanostructures 50 may have a cross section patterned bythe photolithographic process. That is, the nanostructures 50 which passthe surfaces patterned by the photolithographic process may be alsopatterned and thus has cross sections. The patterned cross sections ofthe nanostructures 50 may be exposed to the outside of the matrix 55.The cross sections of the nanostructures 50 and the matrix 55 which arepatterned by the photolithographic process are the same surfaces and oneend of each of the nanostructures 50 is exposed by patterning to theoutside of the matrix 55.

Opposite ends of some nanostructures 50 may intersect side surfaces ofthe first electrode pattern 21, and one of opposite ends of somenanostructures 50 may intersect a side surface of the first electrodepattern 21 and the other end thereof may be located inside the firstelectrode pattern 21. Furthermore, both opposite ends of each of theremaining nanostructures 50 may be located inside the first electrodepattern 21.

Nanostructures 50, opposite ends of which intersect side surfaces of thefirst electrode pattern 21 among the nanostructures 50 may be referredto as first nanostructures 51. The remaining nanostructures 50 exceptthe first nanostructures 51 may be referred to as second nanostructures53.

That is, nanostructures 50, at least one of opposite ends of which islocated inside the first electrode pattern 21 among the nanostructures50 may be defined as the second nanostructures 53. In other words, thesecond nanostructures 53 may include nanostructures, one of oppositeends of which intersects a side surface of the first electrode pattern21 and the other end of which is located inside the first electrodepattern 21, and nanostructures, both opposite ends of which are locatedinside the first electrode pattern 21 among the plurality ofnanostructures 50.

First, the first body region 22 will be described as an example. Thefirst nanostructures 51 included in the first body region 22 may bedefined as nanostructures, both opposite ends of which are in contactwith edges of the first body region 22 among the plurality ofnanostructure 50. Since the first body region 22 is defined as a unitconductive pattern, the first nanostructures 51 may be nanostructures,both opposite ends of which are in contact with edges of the unitconductive pattern among the plurality of nanostructures 50. Each of thefirst nanostructures 51 may include a first end 51 a and a second end 51b. The first end 51 a of the first nanostructure 51 may intersect thefirst side surface 22 a of the first body region 22. The second end 51 bof the first nanostructure 51 may intersect the third side surface 22 cof the first body region 22. Although it is illustrated that oppositeends of the first nanostructure 51 intersect the first side surface 22 aand the third side surface 22 c facing each other, the opposite ends ofthe first nanostructure 51 may intersect two adjacent side surfaces ofthe first body region 22.

Although not shown, a straight line connecting the first end 51 a andthe second end 51 b may intersect the first nanostructure 51. That is,when the straight line connecting the first end 51 a and the second end51 b is drawn, the first nanostructure 51 may intersect the straightline at at least one point. The at least one point may be a point otherthan the first end 51 a and the second end 51 b.

Since the first nanostructure 51 may have an arbitrary curved shape, thefirst nanostructure 51 may have a region located between the first end51 a and the second end 51 b and intersecting the straight line betweenthe first end 51 a and the second end 51 b. The straight line betweenthe first end 51 a and the second end 51 b may be a virtual line.

The second nanostructure 53 may include a first end 53 a and a secondend 53 b. The first end 53 a of the second nanostructure 53 mayintersect the first side surface 22 a of the first body region 22. Thesecond end 53 b of the second nanostructure 53 may be located inside thefirst body region 22.

A ratio of the first nanostructures 51 to all the nanostructures 50 maybe 70% or more. A ratio of first nanostructures 51 to all nanostructures50 formed in the first body region 22 may be 70% or more.

That the ratio of the first nanostructures 51 to all the nanostructures50 is high may be understood to mean that the nanostructures 50 areformed to be long. Thus, the number of intersecting nanostructures 50per unit number of nanostructures 50 may be increased by forming thenanostructures 50 to be long. As the number of intersectingnanostructures 50 per unit number of nanostructures 50 is increased, thenumber of charge moving paths between the nanostructures 50 increasesand thus the conductivity of the first electrode pattern 21 may beimproved.

When the ratio of the first nanostructures 51 to all the nanostructures50 is less than 70%, the effect of improving the conductivity of thefirst electrode pattern 21 is low. Thus, the effect of improving theconductivity of the first electrode pattern 21 may be increased bysetting the ratio of the first nanostructures 51 to all thenanostructures 50 in the first body region 22 to be 70% or more.

The first body region 22 may have a first width d1, and the firstconnection part 23 may have a second width d2. The first width d1 may beunderstood as the distance between opposite side surfaces of the firstbody region 22. That is, the first width d1 may be the distance betweenthe first side surface 22 a and the third side surface 22 c of the firstbody region 22.

The first width d1 may be different from the second width d2. A ratio ofthe second width d2 to the first width d1 may be 50 to 60%. The firstwidth d1 may be 50 um to 60 um, and the second width d2 may be 30 um.

The first connection part 23 may be formed in a tetragonal shape. Sincethe first connection part 23 connects two adjacent first body regions22, the first connection part 23 may have two side surfaces. The firstconnection part 23 may have a first side surface 23 a and a second sidesurface 23 b which are not in contact with the first body region 22. Thesecond width d2 may be defined as the distance between the first sidesurface 23 a and the second side surface 23 b.

Similarly, the first side surface 23 a and the second side surface 23 bof the first connection part 23 may be cross sections patterned by thephotolithographic process.

The first connection part 23 may also include a first nanostructure 51and a second nanostructure 53. A nanostructure, opposite ends of whichintersect side surfaces of the first connection part 23 among theplurality of nanostructures 50 is defined as the first nanostructure 51of the first connection part 23. That is, the first nanostructure 51 ofthe first connection part 23 may be defined as a nanostructure, bothopposite ends of which are in contact with edges of the first connectionpart 23. A nanostructure, at least one end of which is located insidethe first connection part 23 among the plurality of nanostructures 50may be defined as the second nanostructure 53 of the first connectionpart 23.

In the drawings, a first end 51 a of the first nanostructure 51 of thefirst connection part 23 may intersect the first side surface 23 a ofthe first connection part 23, and a second end 51 b of the firstnanostructure 51 of the first connection part 23 may intersect thesecond side surface 23 b of the first connection part 23.

The first end 53 a of the second nanostructure 53 may be located insidethe first connection part 23. The second end 53 b of the secondnanostructure 53 may intersect the second side surface 23 b of the firstconnection part 23.

A ratio of first nanostructures 51 to all nanostructures 50 formed inthe first connection part 23 may be different from that of the firstnanostructures 51 to all the nanostructures 50 formed in the first bodyregion 22.

The ratio of the first nanostructures 51 in the first connection part 23may be greater than that of the first nanostructures 51 in the firstbody region 22. The ratio of the first nanostructures 51 in the firstconnection part 23 may be 80% or more.

The number of intersecting nanostructures 50 per unit number ofnanostructures 50 may be increased by setting the ratio of the firstnanostructures 51 in the first connection part 23 to be 80% or more.Thus, the number of charge moving paths between the nanostructures 50may increase and as a result, the effect of improving the conductivityof the first electrode pattern 21 may be achieved.

By setting the ratio of the first nanostructures 51 in the firstconnection part 23 which has a relatively small width and in whichcracks are thus likely to occur due to external shocks to be 80% ormore, the nanostructures 50 may serve as a frame to reduce theoccurrence of cracks. Even if cracks occur, nanostructures 50 formed ina region in which cracks occur may provide a charge moving path and thusan electrical disconnection error may be prevented from occurring.

Although FIGS. 4 and 5 have been described above with respect to thefirst electrode pattern 21, the second electrode pattern 31 may have thesame technical characteristics as those of the first electrode pattern21.

Although a case in which the first body region 22 and the second bodyregion 32 have a tetragonal shape has been described in the aboveembodiment, the first body region 22 and the second body region 32 mayhave a polygonal shape, a circular shape, or an oval shape. That is, theunit conductive pattern may have a polygonal shape, a circular shape, oran oval shape. When the first body region 22 and the second body region32 have the circular shape or the oval shape, the first nanostructure 51may be defined as a nanostructure, both opposite ends of which are incontact with edges of the first body region 22 and the second bodyregion 32.

FIG. 6 is a diagram illustrating a field emission device according to anembodiment.

Referring to FIG. 6, a field emission device 70 according to anembodiment includes a nozzle 71, a syringe 72, a syringe pump 73, apower supply unit 74, and a collector 75.

The nozzle 71 may be connected to the syringe 72. The syringe 72 may beconnected to the syringe pump 73. A spinning solution is injected intothe syringe 72. The syringe pump 73 applies pressure to the syringe 72.The spinning solution injected into the syringe 72 may be transferred tothe nozzle 71 due to the pressure applied by the syringe pump 73.

The spinning solution may include a metal material and a polymer.

The syringe pump 73 may adjust pressure to be applied to the syringe 72to spray a constant amount of the spinning solution via the nozzle 71.

The power supply unit 74 may be electrically connected to the nozzle 71and the collector 75, and apply a voltage to the nozzle 71 and thecollector 75.

When the power supply unit 74 applies the voltage to the nozzle 71 andthe collector 75, an electric field is formed between the nozzle 71 andthe collector 75. When the intensity of the electric field is the sameas a surface tension of the spinning solution, an end part of the nozzle71 is covered with the spinning solution having electric charge.

In this case, when a voltage greater than or equal to the surfacetension of the spinning solution is applied, nanofibers 80 are sprayedin a direction of the collector 75 which is a ground-voltage direction.The above method of forming the nanofibers 80 is referred to aselectro-spinning.

Although electro-spinning has been described above as an example of amethod of forming the nanofibers 80 in one embodiment, the presentinvention is not limited thereto.

The nanofibers 80 having a small width and a high aspect ratio may beformed by controlling, by the electro-spinning, a voltage to be appliedby the power supply unit 74 and pressure to be applied by the syringepump 73.

The nanofibers 80 formed by the electro-spinning may include the metalmaterial and the polymer.

Thereafter, the nanostructures 50 including only the metal material ofFIGS. 4 and 5 may be formed by removing the polymer from the nanofibers80.

The optical transmissivity of an electrode pattern may be improved byforming the nanostructures 50 having a small width through the aboveprocess.

Furthermore, since the nanostructures 50 having a high aspect ratio,i.e., the nanostructures 50 which are long, may be formed, the number ofintersecting nanostructures 50 per unit number of nanostructures 50increases. As the number of intersecting nanostructures 50 per unitnumber of nanostructures 50 increases, the number of charge moving pathsbetween the nanostructures 50 increases. Accordingly, the conductivityof an entire conductive pattern may be improved.

The polymer may be removed from the nanofibers 80 through heattreatment.

During the removing of the polymer from the nanofibers 80, intersectingnanostructures may be electrically connected to each other.

In one embodiment, since the effect of improving the conductivity of aconductive pattern may be achieved through the removing of the polymer,conductivity may be improved more easily than a process of processing anintersection region of silver nanowires having an organic film onsurfaces thereof. Thus, manufacturing costs may be reduced. Furthermore,the removing of the polymer and the processing of the intersectionregion may be simultaneously performed through one process, therebyincreasing manufacturing yield.

FIG. 7 is a perspective view of a display device to which a touch panelis applied, according to an embodiment.

Referring to FIG. 7, a display device 100 may include an input button110 to which a command is input from the outside, a camera 120configured to capture still images and moving images, and a speaker 130through which sound is output.

The display device 100 may include the touch panel 1 as described aboveand a display panel (not shown). The touch panel 1 may be formed on afront surface of the display panel and thus a cover glass 70 may beexposed on a top surface of the display device 100. Alternatively, thedisplay panel may be attached to the touch panel 1.

The display panel may display an image. The display panel may be aliquid crystal display panel or an organic light-emitting display panel,and may be applied to various products such as a mobile phone, atelevision (TV), and a navigation device.

Although a display device has been described above as an example of adevice to which touch panels according to embodiments of the presentinvention are applicable, the device is not limited to the displaydevice and may be used in various products such as a keypad, a touch padfor a laptop computer, and a touch input device for a vehicle.

While the structure and features of the present invention have beendescribed above with respect to embodiments of the present invention, itwould be apparent to those of ordinary skill in the art that the presentinvention is not limited thereto and may be changed or modifiedvariously without departing from the idea and scope of the presentinvention. Accordingly, it should be understood that such changes ormodifications fall within the scope of the invention as defined in theappended claims.

The invention claimed is:
 1. A conductive pattern, comprising: at least two unit conductive patterns, wherein the unit conductive patterns include a plurality of nano structures having both ends, and a first ratio of a number of the plurality of nano structures of the unit conductive patterns in which both ends are in contact with side surfaces of the unit conductive patterns to a total number of the plurality of nano structures of the unit conductive patterns is 70% or more; and a connection portion connecting the at least two unit conductive patterns, wherein a width of the connection portion is 50% to 60% of a width of the unit conductive patterns, wherein the connection portion includes a plurality of nano structures having both ends, and wherein a second ratio of a number of the plurality of nano structures of the connection portion in which both ends are in contact with side surfaces of the connection portion to a total number of the plurality of nano structures of the connection portion is different from the first ratio.
 2. The conductive pattern of claim 1, further comprising a matrix containing the plurality of nano structures of the unit conductive patterns.
 3. The conductive pattern of claim 2, wherein the matrix is formed to extend continuously over the unit conductive patterns and the connection portion.
 4. The conductive pattern of claim 2, wherein an end of at least a portion of the plurality of nano structures of the unit conductive patterns in contact with a side surface of the unit conductive patterns is exposed to an outside of the matrix.
 5. The conductive pattern of claim 2, wherein the matrix includes a conductive material.
 6. The conductive pattern of claim 2, wherein the matrix prevents oxidation of the plurality of nano structures of the unit conductive patterns.
 7. The conductive pattern of claim 2, wherein the plurality of nano structures of the unit conductive patterns is dispersed inside the matrix.
 8. The conductive pattern of claim 1, wherein the plurality of nano structures of the unit conductive patterns includes a first nano structure and a second nano structure, wherein an end of the first nano structure and an end of the second nano structure are in contact with the same side surface of the unit conductive patterns, and wherein the first nano structure and the second nano structure are electrically connected directly to each other inside the unit conductive patterns.
 9. The conductive pattern of claim 1, wherein the plurality of nano structures of the unit conductive patterns is formed in a cylindrical shape.
 10. The conductive pattern of claim 1, wherein the plurality of nano structures of the unit conductive patterns comprises a silver (Ag) material.
 11. The conductive pattern of claim 1, wherein the plurality of nano structures of the unit conductive patterns is formed by electro-spinning.
 12. The conductive pattern of claim 1, wherein at least a portion of the plurality of nano structures of the unit conductive patterns in which both ends are in contact with side surfaces of the unit conductive patterns has a curved shape and intersects a virtual straight line between the both ends at one or more points other than the both ends.
 13. The conductive pattern of claim 1, wherein the second ratio is 80% or more. 